1. Field of the Invention
The present invention relates generally to filtration systems, and more particularly is a filtration system in which a self-cleaning filter element is utilized in a vortex tank.
2. Description of the Prior Art
In any scenario in which large amounts of water are utilized, a filtering system is necessary to keep the water clean and free of contaminants. Such scenarios include swimming and wading pools, fountains, fish tanks and ponds, and other aquaculture applications. The present invention was developed specifically for fish tanks and ponds, but is clearly applicable in any application requiring high volume filtering.
Most filtering systems utilize a filter tank with a filtering medium suspended in an interior of the tank. The filtering medium must be formed from a particulate material so that water can flow through the medium. Some media commonly used for filtering are diatomaceous earth, sand, gravel, plastic pellets, and plastic mats. The filter media remove contaminants from the water by trapping the contaminating material on the individual particles of the filter medium. After the filter system has operated for some time, there is clearly the danger of the filter being clogged by the trapped contaminants. Therefore these types of filtering media require periodic cleaning.
The method most commonly used for cleaning the filter medium in a filter tank is backwashing. Backwashing typically involves simply reversing the direction of water flow through the interior of the filter tank so that the trapped particulate matter is washed back out of the tank. Apart from the aggregation problems inherent in the use of particulate media that reduces the cleaning effect of backwashing, backwashing by necessity involves shutting down the filtering system for at least some period of time. The system shutdown for maintenance must be scheduled at regular intervals. Cleaning a filtration system is thus susceptible to errors and omissions not only in the operation itself, but also in remembering to perform the operation at the proper intervals. Moreover, backwashing systems normally require large amounts of fresh water to operate.
Accordingly, it is an object of the present invention to provide a filtering method that gently removes particulate matter from an aquaculture system so that solid waste is not broken apart during the filtration process.
It is a further object of the present invention to provide a filtering device that is cost and energy efficient.
It is a still further object of the present invention to provide a filtering system that is compatible with both fresh and salt water applications, and is environmentally safe.
The present invention is a filtration system utilizing a vortex mechanical power filter. The filter unit is supported by a polyurethane ring float so that the filter unit is self-adjusting. That is, the filter unit will automatically come to a proper equilibrium level position irrespective of variations in the working water level in the system.
A single pump is used to move water through the system. Water to be filtered comes from a supply, typically a fish pond, via gravity feed to the filter unit. The supply line is situated so that the supplied water impinges the filter unit at an angle, supplying power to cause rotation of the filter unit. Additional power is supplied for rotation of the filter unit by a screen vortex disrupter that is placed in the center of the filter drum. The vortex disrupter transfers energy from the suction vortex caused by the pump drawing water through a center standpipe to the filter drum, further aiding rotation of the filter drum. The vortex disrupter maintains the vortex beneath the surface of the water so that the system does not suck air.
As the system operates, a water jet assembly sprays a plurality of water jets onto a filter screen to gently clean waste from the screen. The nozzle pressure and velocity of the jets are controlled by a flow valve and by varying nozzle sizes. The water jet assembly uses clean water diverted from the filter unit.
An advantage of the present invention is that the system operates continuously, with no need for backwashing.
Another advantage of the present invention is that the gentle cleaning action allows fecal waste to be removed from the water in the system without first breaking up the fecal matter.
A still further advantage of the present invention is that it can operate with a single pump.
Another advantage of the present invention is that it can be used in many different high volume applications with only minor changes in the design of the system.
Yet another advantage of the present invention is that it is compatible with both salt water and fresh water applications.
Still another advantage is that the filter system can be left unattended for long periods of time. The system requires only very low maintenance.
An additional benefit of the system is that the incoming water enriches the oxygen level, providing a xe2x80x9cstewxe2x80x9d for aerobic bacteria living on the micro screen filter.
These and other objects and advantages of the present invention will become apparent to those skilled in the art in view of the description of the best presently known mode of carrying out the invention as described herein and as illustrated in the drawings.